void shuru () {
    char ch = getch ();
    if (ch == 75) {
        if (changdi[x + fxfx[0][0]][y + fxfx[0][1]] == 1 | changdi[x + fxfx[0][0]][y + fxfx[0][1]] == 2) {
            fangx = nextfx = 0;
        } else {
            nextfx = 0;
        }
    } else if (ch == 80) {
        if (changdi[x + fxfx[1][0]][y + fxfx[1][1]] == 1 | changdi[x + fxfx[1][0]][y + fxfx[1][1]] == 2) {
            fangx = nextfx = 1;
        } else {
            nextfx = 1;
        } 
    } else if (ch == 77) {
        if (changdi[x + fxfx[2][0]][y + fxfx[2][1]] == 1 | changdi[x + fxfx[2][0]][y + fxfx[2][1]] == 2) {
            fangx = nextfx = 2;
        } else {
            nextfx = 2;
        }
